For this brief video, a mouthpiece and vinyl tubing have been combined to illustrate some basic principles regarding the generation of musical notes. It reminds me of the unusual musical creations of Gerard Hoffnung, who commissioned the "Grand, Grand Overture" by Malcolm Arnold (scored for three vacuum cleaners and an electric floor polisher). One instrument Hoffnung devised was the "hosepipe" - a mouthpiece attached to a garden hose.

And a hat tip to Yucatanstan [nice name!] for identifying the instructor as Dr. John Winkler, Professor of Trumpet at West Virginia University's College of Creative Arts.

"The funnel makes it louder" implies amplification, which isn't strictly true. The funnel helps match the impedance of the tube with that of the surrounding air, resulting in a more efficient transfer of energy. It's how old phonographs got so much sound from a vibrating needle - impedance matching.

This is a tool I use frequently with my brass pupils when I'm teaching about the harmonic series and natural brass instruments! A lot of people stick a funnel in the end to make it look more like a real instrument, but that's optional! Mine is clear tubing my mother got me from the hospital... I don't care to know what it was used for; most people however, use a plain old garden hose!